--Direct Compression stress and deformation
1. Using reasonable design assumptions, propose a diameter for the shaft based on direct normal stress. Be sure to state your safety factor and reasons for picking that factor.
2. Determine the stress concentration factor Kt for a sled-runner keyseat (same as in bending).
3. Using the stress concentration factor Kt just determined, adjust your recommendation for shaft diameter.
4. Based on your recommended diameter, compute the deformation δc due to force P.
Torsional shear stress and deformation
5. Compute the torque TB and TC due to tensile forces in the belts at point B and C, respectively.
6. Draw the torque diagram to show the level of torque in all segments of the shaft.
7. Based on your recommended diameter found in step 4 above, compute the nominal torsional stress Bnom and Cnom on the outer surface of the shaft for cross sections passing through points B and C due to the torque TB and TC.
8. Compute the angle of twist θBC of the cross section passing through B with respect to that passing through point C.
9. Determine the stress concentration factor Kt, in torsion, for a sled-runner keyseat.
10. Using the stress concentration factor Kt just determined, calculate the shear stresses B and C on the outer surface of the shaft for cross sections passing through points B and C, respectively.
11. If necessary, adjust your recommended diameter to allow for the direct shear stress. Reiterate the calculations for σ, δc, and B.
12. Determine the force F that the shaft exerts on the key
13. Suggest the dimensions (length, width, and height) of the key if it was made of steel. ( there are many possible solutions)
Are the values of the deformation δc due to the compressive force P, and the angle of twist θBC acceptable for a power transmission shaft such as the one under consideration? Why?
What considerations and standards did you use to determine safety factors